1. Field of the Invention
The present invention relates to watermarking signals and more specifically to a presale watermarking of digital files prior to compression.
2. Introduction
Current music industry practice is to “sue first and ask questions later”. For example, when attempting to prevent piracy or unauthorized copying of audio files, often any MP3 file is assumed to have illegal providence. In other words, the source of that particular MP3 file is assumed to be illegal rather than from the authorized owner or authorized distributor under copyright law. In any individual case, proving or disproving such assumption can be problematic. Digital rights management (DRM) schemes essentially sidestep this issue by trying to make illegal use technically impossible. There are problems with these approaches to protecting copyrighted information. For example, clumsy technologies that result from DRM schemes render an end user's experience in purchasing and downloading digital files such as MP3 music files so difficult that the market can be stifled. On the other hand, users have incentives to find DRM work-arounds which infringe on the copyright owner's rights. What is needed in the art is a mechanism by which copyrighted information can be tracked to the original purchaser while not restricting the use of the distributed digital file or its functionality in any way.